How to delete records using checkbox in asp.net C#

Dear Experts,
plz can u suggest me C# code...for delete using checkbox in asp.net using c#..
And also i want to display here name and image.
I tried this code but not cmg..
this is my design page...

<div>
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" DataKeyNames="id" DataSourceID="SqlDataSource1">
        <Columns>
        <asp:TemplateField>
        <ItemTemplate>
        <asp:CheckBox ID="chkdelete" runat="server" />

        </ItemTemplate>

        </asp:TemplateField>
        <asp:BoundField DataField="id" HeaderText="id" />
        <asp:BoundField DataField="Name" HeaderText="Name" />
        <asp:BoundField DataField="Image" HeaderText="Image" />
        </Columns>

        </asp:GridView>

        <asp:SqlDataSource ID="SqlDataSource1" Runat="server"
    SelectCommand="SELECT id, Name, image FROM showdetails"
    DeleteCommand="DELETE FROM showdetails WHERE id = @id"
    ConnectionString="<%$ ConnectionStrings:sss %>" >


</asp:SqlDataSource>
    </div>
    <asp:Button ID="btndelete" runat="server" Text="Delete"
        onclick="btndelete_Click" />

    </form>

And My asp.cs page

protected void btndelete_Click(object sender, EventArgs e)
    {
        foreach (GridViewRow row in GridView1.Rows)
        {
            CheckBox checkbox = (CheckBox)row.FindControl("chkdelete");


            if (checkbox.Checked)
            {

                int id = Convert.ToInt32(GridView1.DataKeys[row.RowIndex].Value);
                SqlDataSource1.DeleteParameters["id"].DefaultValue = id.ToString();
                SqlDataSource1.Delete();
            }

}

Tags: C# 3.5, ASP.NET